High-Performance Supercapacitors of N-Doped Graphene Aerogel and Its Nanocomposites

Nitrogen-doped graphene aerogel (NG(ae)) with three-dimensional interconnected structure was synthesized by a hydrothermal reduction of graphene oxide with hydrazine and a following freezing-dry method. The 3D morphology of conductive NG(ae) provides diffusion pathways for electron and ion transportation. Also, the nitrogen-containing groups can store charges via surface redox reactions. The as-fabricated NG(ae) symmetric supercapacitor (CR2016) in 1 M H2SO4 electrolyte provides a specific capacitance of 470.45 F g(-1) at an applied current of 1 mA with maximum energy density and power density of 41.71 Wh kg(-1) and 2442.47 W kg(-1), respectively. Incorporating MnO2 and polyaniline to NG(ae) structure can provide higher specific power and/or energy. The as fabricated supercapacitors in this work may be practically used in high energy and power applications.